> ## Documentation Index
> Fetch the complete documentation index at: https://developer.meow.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Meow API reference: endpoints, payloads, and examples

> Complete reference for Meow API endpoints covering accounts, balances, transfers, contacts, billing, invoicing, partner onboarding, and routing checks.

## Overview

The Meow API provides comprehensive financial services and billing capabilities for businesses.

### Core Features

* **Financial Data Access**: Securely access account information, transactions, balances, and payment networks
* **USDC Operations**: Create and manage cryptocurrency contacts, initiate USDC transfers across multiple blockchain networks

### Billing API

The Billing API enables businesses to streamline their invoicing and payment collection:

* **Product Management**: Create and manage products with customizable pricing
* **Customer Management**: Maintain invoicing customers with billing addresses
* **Invoice Creation**: Generate invoices with line items, discounts, and custom notes
* **Flexible Payment Options**: Accept payments via bank transfer, ACH, cards, international wires, and USDC
* **Collection Accounts**: Configure accounts for automated payment collection

## Authentication

All API requests require an API key passed in the `x-api-key` header. See the [Authentication](/authentication) guide for details.

## Base URLs

| Environment | URL                               |
| ----------- | --------------------------------- |
| Production  | `https://api.meow.com/v1`         |
| Sandbox     | `https://api.sandbox.meow.com/v1` |
| Development | `https://api.dev.meow.com/v1`     |

## Multi-Entity Access

For API keys with access to multiple entities, include the `x-entity-id` header to scope requests to a specific entity.